The invention relates to snow groomers and to implement controls for snow groomers and for other utilitarian motorized vehicle.
Snow groomers are tracked vehicles used for preparing snow surfaces such as ski slopes, cross-country ski trails, snow mobile trails and the like to obtain a smooth compacted snow covered surface of a desired configuration to facilitate the practice of winter sports and reduce the risks of accidents while practicing these winter sports. Snow groomers are normally equipped with a variety of snow grooming and conditioning implements which are operated from the operator""s cabin enabling the operator to control these implements while the snow groomer is moving.
Joysticks are commonly used to control work implements on snow groomers and on a variety of utilitarian vehicles. The lateral motion and the fore and aft motion of the joystick normally control the hydraulic system of a single work implement. In some instances, the joystick will be adapted to control a second implement by rotating the joystick clockwise or counterclockwise while still controlling the primary implements.
Joysticks are also constructed with a base featuring a cardan joint or universal joint to provide motion of the stick in all directions and feature electric position sensors linked to the shaft of the joystick as is disclosed U.S. Pat. No. 5,576,704 to Baker et al. The relative position of the joystick in relation to the position sensors is translated by a control means into motion of a specific work implement and in some instances, the joystick affords some degree of control over the acceleration and deceleration of the specific work implement. U.S. Pat. No. 4,574,651 to Lennart et al. discloses a control stick for a fighter aircraft that controls a plurality of functions. An array of selector switches and buttons are disposed either on the handle or in close proximity of the handle enabling the pilot to control many functions without removing his hand from the control stick. The control stick has two separate portions. The lower portion only moves fore and aft along a single axis and controls the engine throttle. The upper portion of the control stick is swingable along two axes similar to a conventional joystick and its sole purpose is to control the radar orientation and range. Buttons and switches on the control stick unit operate control instrumentalities and radar mode selection while the joystick maintains radar control.
UK Patent Application GB 2 244 742A discloses a joystick for controlling a cleaning vehicle. The joystick uses a first microswitch 170 and a second microswitch 190, both connected to a control module 198 to control various cleaning implements and operations.
In the presence of a plurality of independent work implements requiring joystick controls, a plurality of joysticks are usually installed, one for each implement. It is not uncommon to see up to five joysticks in a single operator""s cabin. This array of joystick controls is cumbersome and less than efficient in a small operator""s cabin.
It is thus an object of the invention to provide an improved snow grooming vehicle.
It is another object of the invention to provide a multifunction joystick control system adapted to selectively control a plurality of independent functions.
It is another object of the invention to provide a multifunction joystick control system adapted to combine hydraulic control for some implement functions with electrical control for other implement functions.
Yet another object of the invention is to provide improved implements controls for utilitarian vehicles.
It is also an object of the invention an improved snow grooming vehicle adapted to selectively control a plurality of independent functions using a single multifunction joystick.
As embodied and broadly described herein, the invention provides a snow grooming vehicle having a frame supported and propelled by ground engaging tracks, an operator""s cabin mounted to the frame, implement coupling means for at least one snow working implement carried by the frame, and at least two sets of implement actuators which are subject to operational control by the operator from within the operator""s cabin. Each set of implement actuators being controllable by a joystick independently of the control of any other set of implement actuators. The snow grooming vehicle has an engine for driving the ground engaging tracks, the joystick has a hand grip portion positioned for convenient manipulation by the operator when sitting into the operator""s cabin in a normal command position. Electrical transducer means are operatively associated with the joystick for generating an electrical signal representative of the position of the joystick. Manual control switching means operable by the operator from its normal command position are provided for selecting a set of implement actuators of which the operator desires to change the condition by means of the joystick thereby adjusting the position or setting of an implement according to the position of the joystick. There is a controller having at least two inputs and one output and generating an output signal representative of the position of the joystick for operatively controlling the set of implement actuators selected by the operator. The manual control switching means are coupled to a first input of said controller; the electrical signal produced by the electrical transducer means are coupled to a second input of the controller, whereby while the manual control switching means is actuated, the controller generates an output signal representative of the position of the joystick which is used to operatively control a predetermined set of implement actuators; the joystick being adapted to control at least one other set of implement actuators when the manual control switching means is not actuated.
Preferably, one snow grooming implement is a front snow blade and the other set of implement actuators which are controlled by the joystick when the manual control switching means is not actuated consists of a first hydraulic cylinder which sets the height of the front snow blade and a second hydraulic cylinder which sets the tilt angle of the front snow blade.
Advantageously, the first and second hydraulic cylinders are controlled by a set of hydraulic control valves which are mechanically linked to, and controlled by the joystick and rendered inoperative whenever the manual control switching means is actuated.
As embodied and broadly described the invention also provides a snowgrooming vehicle having an internal combustion engine, a frame, an operator""s cabin supported by the frame, a set of ground engaging tracks, a drive mechanism linking the engine to the ground engaging tracks enabling the vehicle to move on snow, implement coupling means for at least one implement, the implement being subject to functional control by the operator from within the operator""s cabin, a multifunction joystick control system for selectively controlling an implement carried by the implement coupling means. The multifunction joystick control system comprises a joystick having a hand grip portion positioned for convenient manipulation by the operator when sitting into the operator""s cabin in a normal command position, manual control switching means operable by the operator from the normal command position for selecting a function of an implement that the operator desires to control by normal bi-axial manipulation of the joystick, a controller for generating an output signal which is used for effecting the operational control of the function of an implement selected by the operator whenever the manual control switching means is actuated. The multifunction joystick control system is adapted to also control the operation of at least one other function of an implement by normal bi-axial manipulation of the joystick while the manual control switching means is not actuated.
Preferably, the multifunction joystick control system further comprises a set of electrical transducers operatively associated with the joystick for generating an electrical signal representative of the position of the joystick, the electrical signal generated by the set of electrical transducers being coupled to a second input of the controller.
Advantageously, the manual control switching means generates an electrical signal representative of the selected function of an implement, and this electrical signal generated by the manual control switching means is coupled to a first input of the controller.
The invention also provides a multifunction joystick control system for a snow grooming vehicle which has a frame, ground engaging tracks, an operator""s cabin, an engine for driving the vehicle, implement coupling means for at least one snow grooming implement and at least two sets of implement actuators separately controlled by the operator, each set of implement actuators being controllable by a joystick. The multifunction joystick control system has a joystick having a hand grip portion positioned for convenient manipulation by the operator when sitting into the operator""s cabin in a normal command position, a set of electrical transducers operatively associated with the joystick for generating an electrical signal representative of the position of the joystick, a first manual control switching means operable by the operator from the normal command position for selecting a first set of implement actuators that the operator desires to operationally control, the first manual control switching means generating an electrical signal representative of the first set of implement actuators, and a controller having at least two inputs and one output and generating an output signal for effecting the operational control of the set of implement actuators selected by the operator. The electrical signal generated by the first manual control switching means is coupled to a first input of the controller. The electrical signal generated by the set of electrical transducers is coupled to a second input of the controller. The controller generates a first output signal when the first manual control switching means is actuated, the first output signal being representative of the position of the joystick and being used to control the operation of the first set of implement actuators. The multifunction joystick control system is adapted to control the operation of at least one other set of implement actuators as a function of the position of the joystick when the first manual control switching means is not actuated.
Preferably, the other set of implement actuators consists of a set of hydraulic cylinders which require control by the operator for proper operation of the utilitarian vehicle. The multifunction joystick control system also comprises a hydraulic circuit for operating the hydraulic cylinders, control valve means operatively associated with the joystick for controlling hydraulic fluid supply through said hydraulic circuit to the hydraulic cylinders as a function of the position of said joystick and disabling means for disabling the control valve means when the first manual control switching means is actuated.
Advantageously, the manual control switching means comprises at least one push button located on the hand grip portion of the joystick.
As embodied and broadly described, the invention also provides a multifunction joystick control system for a utilitarian vehicle having at least one implement and at least two sets of implement actuators which are subject to operational control by the operator from within an operator""s cabin in the utilitarian vehicle. Each set of implement actuators is controllable by a joystick independently of the control of any other set of implement actuators. The multifunction joystick control system features a joystick having a hand grip portion positioned for convenient manipulation by the operator when sitting into the operator""s cabin in a normal command position, a set of electrical transducers operatively associated with the joystick for generating an electrical signal representative of the position of the joystick, a first manual control switching means operable by the operator from the normal command position for selecting a first set of implement actuators that the operator desires to operationally control, the first manual control switching means generating an electrical signal representative of the first set of implement actuators, a controller having at least two inputs and one output and generating an output signal for effecting the operational control of the set of implement actuators selected by the operator. The electrical signal generated by the first manual control switching means is applied to a first input of the controller. The electrical signal generated by the set of electrical transducers being applied to a second input of the controller. The controller generates a first output signal when the first manual control switching means is actuated, the first output signal being representative of the position of said joystick and being used to control the operation of the first set of implement actuators. The multifunction joystick control system is adapted to control the operation of at least one other set of implement actuators when the first manual control switching means is not actuated.
Other objects and features of the invention will become apparent by reference to the following description and the drawings.